package com.code.generate.util;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.LinkedList;
import java.util.concurrent.ConcurrentHashMap;

public class test {
    public static void main(String[] args) {
        HashMap<Object,Object> hashMap = new HashMap<>();
        hashMap.put("k","v");
        hashMap.get("k");
        hashMap.containsValue("");
        hashMap.containsKey("");
        hashMap.keySet();
        hashMap.remove("k");

        Hashtable<Object,Object> hashtable = new Hashtable();
        hashtable.put("k","v");
        hashtable.get("k");
        hashtable.remove("k");

        ConcurrentHashMap<Object,Object> concurrentHashMap = new ConcurrentHashMap<>();
        concurrentHashMap.put("k","v");
        concurrentHashMap.get("k");
        concurrentHashMap.remove("k");

        ArrayList<Object> arrayList = new ArrayList<>();
        arrayList.add("k");
        arrayList.get(0);
        arrayList.remove("k");

        LinkedList<Object> linkedList = new LinkedList<>();
        linkedList.add("k");
        linkedList.get(0);
        linkedList.remove("k");

        "".indexOf("");
    }
}
